Cap and tube assemblies which carry medicines, vitamins, and the like have obtained significant interest in the pharmaceutical industry. Not only is there a concern for resistance to undesirable tampering, such as by a child, there is increasing interest in insuring that the entire dose contained in the container is delivered to the patient and that no parts of the container itself contact the patient.
In my recent patent, U.S. Pat. No. 4,867,326, I have provided an excellent design for a child resistant cap. The design described in my patent is of great value in providing a product wherein there is easy inspection of unit dose sterile medicaments in a cap and tube assembly which is child resistant and suitable for a high reliability pass/fail inspection.
Depending upon the size of the tube, the thickness of the thin wall, and the shape of the piercer, tearing the plastic thin wall causes pieces to break off. These small pieces of plastic are inert, and normally are not harmful. However, particularly when the contents are eye drops, it would be of great advantage if the possibility of small pieces of plastic breaking off could be reduced to the absolute minimum, if not totally eliminated. Accordingly, that is one of the objects of the present invention.
Also, the junction between the tube and the portion of the tube which forms the discharge structure for a cap and tube assembly often times includes a sharp junction, as would necessarily happen if the discharge nozzle was merely joined to the tube using conventional technology. In this case, sometimes when the product is dispensed from the tube, one or two drops are trapped on what becomes a ledge or ring at the junction between the tube and the discharge nozzle. When it is important that the entire dose be received by the user, failure to remove these one or two drops provides a less than complete treatment. Accordingly, it is another object of this invention to provide a design which allows for total evacuation of the tube.
In order to increase the efficiency of cap and tube assemblies during the filling step, particularly when automated assembly is employed, it is necessary to rapidly transfer large quantities of cap and tube assemblies to the filling machine. This is best accomplished by stacking a plurality of assemblies, with the assembled cap and tube being sized to fit inside other unfilled cap and tube assemblies. It is also necessary that these stacked assemblies be readily separable with a minimum amount of force, such as in a gravity feed so that the automated assembly equipment does not become jammed or otherwise malfunctioned. When this stacking feature is contemplated, it is necessary, of course, to size the cap portion so that it fits within the interior of the adjacent tube. Similarly, the cap cannot be so small that it fits into the nozzle. Accordingly, it object of this invention to provide a cap and tube assembly which is suitable for stacking.
When the junction between the tube and the discharge nozzle is a conventional junction, such as when the tube and nozzle are merely joined together, the ring or ridge which is formed at that junction has the potential for the cap becoming stuck in that junction, thereby causing a difficulty in the separation of two stacked assemblies. If the cap strikes the junction between the tube and a nozzle at an angle, there is the very real danger that the cap will become wedged in the orifice, thereby jamming or otherwise delaying the operation of assembly equipment.